The sum of two rational numbers is $\frac{1}{2}$ and one of the numbers is $\frac{-8}{19}$ then the second number is  

Another number be $\text{'}b\text{'}$

The sum of two numbers $a+b=\frac{1}{2}$

One of the number be $a=-\frac{8}{19}$

$-\frac{8}{19}+b=\frac{1}{2}$

$b=\frac{1}{2}+\frac{8}{19}$

$b=\frac{19+16}{38}$

$b=\frac{35}{38}$

$\therefore$  second number $b=\frac{35}{38}$